Noise, resources, and social factors shape space use and movement patterns in a small Amazonian primate

Noisy environments tend to mask sounds and disrupt animal behaviour. One of the most common responses from many animal species to noise is leaving or avoiding the noisiest parts of their ranges. Individuals may alter their movement patterns, either rapidly moving away or changing routes in response to increased noise levels. Here, we tested whether urban-dwelling pied tamarins (Saguinus bicolor): (1) preferentially used quieter areas within their home range, (2) increase travel speed, and (3) alter routes to avoid noise levels. To achieve this, we followed nine pied tamarin groups in five forest fragments within the city of Manaus, Brazil, recording their locations and levels of associated ambient noise levels. We also estimated fruit availability at random points within the group’s home ranges. We found that pied tamarins use the quieter areas of their ranges more intensively, but only if the fruit availability is high. Furthermore, groups did not increase their travel speed or change turning angles in response to noise alone, but travel speed increase in noisier areas closer to the border of their home ranges. Thus, pied tamarins do seem to use the quieter areas of their home ranges, but do not hurry to reach them unless their location lies closer to their home range borders. This may occur because higher noise levels at home-range borders could diminish intergroup communication effectiveness. In general, we found that pied tamarin’s use of space and movement patterns are soundscape-related but mediated by resource availability and social aspects.